Method for determining heat exchange capacity of oil rectifier in refrigeration system, oil rectifier and refrigeration system

Abstract

The present invention discloses a method for determining the heat exchange rate of an oil rectifier in a refrigeration system, an oil rectifier, and a refrigeration system. The method for determining the heat exchange rate of an oil rectifier can be used for a refrigeration system. By setting the oil extraction rate and the steady-state lubricating oil target concentration, and making the target oil recovery amount greater than the mass flow rate of the oil in the refrigeration system, the lubricating oil is extracted during the operation of the refrigeration cycle and sucked into the compressor for reuse. Through multiple refrigeration cycles, the lubricating oil content remaining in the refrigeration system is gradually reduced and prevented from increasing. In this way, on the one hand, good working conditions can be provided for the evaporator, the efficiency of the evaporator can be improved, and sufficient lubricating oil can be ensured in the compressor, thereby improving the reliability of the compressor operation process. On the other hand, the design of the heat exchange rate determination method can provide accurate guidance for the reasonable selection of oil rectifiers, improve the reliability of the refrigeration system, and reduce the waste of resources.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigeration systems, and in particular to a method for determining the heat exchange capacity of an oil rectifier in a refrigeration system, an oil rectifier and a refrigeration system. Background Art

[0002] In the refrigeration system, the compressor needs to be lubricated with lubricating oil during operation. Therefore, a small amount of lubricating oil will enter the refrigeration cycle with the compressor exhaust, resulting in a decrease in the evaporator's working efficiency and affecting the performance of the refrigeration system.

[0003] In the related art, the lubricating oil entering the refrigeration system can be extracted and separated by setting up an oil rectifier (also called an oil extractor). However, there is still a lack of reasonable design for the heat exchange capacity and heat exchange temperature calculation method of the oil rectifier, so it is difficult to provide accurate guidance on the selection of the oil rectifier. Summary of the Invention

[0004] The embodiment of the present invention discloses a method for determining the heat exchange capacity of an oil rectifier in a refrigeration system, which can design a reasonable heat exchange capacity of the oil rectifier so that the oil content of the refrigeration system does not increase during operation.

[0005] To achieve the above objectives, in a first aspect, the present invention discloses a method for determining the heat exchange capacity of an oil rectification device in a refrigeration system, comprising:

[0006] Obtain the following parameters: operating parameters of the refrigeration system and the oil discharge volume E of the refrigeration system oil separator;

[0007] According to the operating parameters of the refrigeration system, the mass flow rate Q of the refrigeration system is obtained. m ;

[0008] According to the oil discharge volume E of the refrigeration system oil separator and the mass flow rate Q of the refrigeration system m , obtaining the mass flow rate F of the oil in the refrigeration system;

[0009] Set the oil extraction rate P and the steady-state lubricating oil target concentration C;

[0010] According to the oil extraction rate P, the steady-state lubricating oil target concentration C, the mass flow rate Q of the refrigeration system m , obtain the target oil recovery F a , and the target oil recovery volume F a Greater than the mass flow rate F of the oil;

[0011] According to the mass flow rate Q of the refrigeration system m and the oil extraction rate P, to obtain the mass flow rate Q of the oil distillation unit r ;

[0012] According to the mass flow rate Q of the oil distillation unitr and the operating parameters of the refrigeration system to obtain the heat transfer capacity K of the oil distillation unit.

[0013] As an optional embodiment, in the embodiment of the present invention, the operating parameters of the refrigeration system include the refrigeration capacity R of the refrigeration system. c , the evaporation temperature of the refrigeration system, and the evaporation heat H of the refrigerant in the refrigeration system at the evaporation temperature of the refrigeration system v .

[0014] As an optional embodiment, in the embodiment of the present invention, the mass flow rate Q of the refrigeration system is m for:

[0015] Q m =R c / H v ;

[0016] Among them, R c is the cooling capacity of the refrigeration system, H v is the evaporation heat of the refrigerant in the refrigeration system.

[0017] As an optional implementation, in an embodiment of the present invention, the mass flow rate F of the oil in the refrigeration system is:

[0018] F=Q m *E;

[0019] Wherein, E is the oil discharge capacity of the oil separator in the refrigeration system.

[0020] As an optional embodiment, in the embodiment of the present invention, the target oil recovery amount F a for:

[0021] F a =Q m *P*C;

[0022] Where P is the oil extraction rate and C is the steady-state target lubricating oil concentration.

[0023] As an optional embodiment, in the embodiment of the present invention, the mass flow rate Q of the oil distillation unit is r for:

[0024] Q r =Q m *P.

[0025] As an optional embodiment, in an embodiment of the present invention, the heat exchange capacity K of the oil rectifier is:

[0026] K=Q r *H v .

[0027] As an optional implementation manner, an embodiment of the present invention includes:

[0028] Obtain the enthalpy value H of the refrigerant at the liquid inlet of the oil distillation device L and the subcooling temperature T of the refrigerant a ;

[0029] According to the mass flow rate Q of the oil distillation unit r , obtain the liquid outlet flow rate Q of the oil distillation unit e ;

[0030] According to the liquid outlet flow rate Q of the oil rectifier e , obtain the enthalpy reduction of the refrigerant in the oil distillation unit H d ;

[0031] According to the enthalpy reduction H of the refrigerant in the oil distillation device d and the enthalpy of the refrigerant at the liquid inlet of the oil distillation device H L , obtain the enthalpy value H of the refrigerant at the liquid outlet of the oil distillation device e ;

[0032] According to the enthalpy value H of the refrigerant at the liquid outlet of the oil distillation device e and the subcooling temperature T of the refrigerant a , calculate the heat exchange temperature difference T of the oil distillation unit d .

[0033] In a second aspect, the present invention further provides an oil rectifier, comprising a first heat exchange side and a second heat exchange side that are independent of each other, wherein the first heat exchange side comprises a liquid supply inlet and a liquid supply outlet, and the second heat exchange side comprises an oil intake port and an oil outlet, and the first heat exchange side and the second heat exchange side are capable of heat exchange;

[0034] The heat exchange capacity of the oil rectifier is determined based on the method for determining the heat exchange capacity of the oil rectifier in the refrigeration system according to the first aspect.

[0035] In a third aspect, the present invention further provides a refrigeration system, comprising:

[0036] a compressor having an air inlet and an air outlet;

[0037] an oil separator connected to the exhaust port of the compressor;

[0038] a condenser, the condenser being connected to the oil separator;

[0039] a liquid reservoir connected to the condenser;

[0040] As in the oil rectifier of the second aspect, the liquid supply inlet is connected to the liquid reservoir, and the oil outlet is connected to the compressor;

[0041] a throttling device connected to the liquid supply outlet of the oil rectifier;

[0042] a circulation barrel, the circulation barrel having a liquid supply port, a liquid outlet port, an air outlet port, an air return port, and an oil drain port, the liquid supply port being connected to the throttling device, the oil drain port being connected to the oil extraction port of the oil rectifier to drain oil into the oil rectifier, and the air outlet port being connected to the air inlet port of the compressor;

[0043] a pump body, the pump body being connected to the liquid outlet of the circulation barrel; and

[0044] An evaporator is connected to the pump body and the air return port of the circulation barrel.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] The embodiment of the present invention provides a method for determining the heat exchange capacity of an oil rectifier in a refrigeration system. The method can be used for the refrigeration system to set the oil extraction rate and steady-state lubricating oil target concentration, and make the target oil recovery amount greater than the mass flow rate of the oil in the refrigeration system, thereby extracting the lubricating oil during the operation of the refrigeration cycle and sucking it into the compressor for reuse. Through multiple refrigeration cycles, the lubricating oil content remaining in the refrigeration system is gradually reduced and prevented from increasing. In this way, on the one hand, it can provide good working conditions for the evaporator, improve the efficiency of the evaporator, ensure that there is sufficient lubricating oil in the compressor, and improve the reliability of the compressor operation process. On the other hand, the design of the heat exchange determination method can provide accurate guidance for the reasonable selection of oil rectifiers, improve the reliability of the refrigeration system, and reduce the waste of resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0048] Figure 1 1 is a flow chart of a method for determining the heat exchange capacity of an oil rectification device in a refrigeration system provided in the first embodiment of the present invention;

[0049] Figure 2 1 is a flow chart of a method for determining the heat exchange temperature of an oil rectifying device in a refrigeration system provided in a second embodiment of the present invention;

[0050] Figure 3Schematic diagram of the block structure of the oil distillation device provided in the third embodiment of the present invention;

[0051] Figure 4 This is a block diagram of a refrigeration system provided by a fourth embodiment of the present invention;

[0052] Figure 5 It is a block diagram of another refrigeration system provided in the fourth embodiment of the present invention.

[0053] Icons: 100, refrigeration system; 10, compressor; 11, air inlet; 12, exhaust port; 20, oil separator; 21, gas outlet; 22, liquid outlet; 30, condenser; 40, liquid reservoir; 50, oil rectifier; 51, first heat exchange side; 511, liquid supply inlet; 512, liquid supply outlet; 52, second heat exchange side; 521, oil intake port; 522, oil outlet; 60, throttling device; 70, circulation barrel; 71, liquid supply port; 72, liquid outlet; 73, air outlet; 74, return air port; 75, oil drain port; 80, pump body; 90, evaporator.

[0054] Main parameter symbol description:

[0055] Refrigeration capacity of the refrigeration system <![CDATA[R c ]]> Heat exchange capacity of oil distillation unit K Heat of evaporation of refrigerant at evaporation temperature <![CDATA[H v ]]> Enthalpy of refrigerant at the liquid inlet of the oil distillation unit <![CDATA[H L ]]> Oil discharge capacity of refrigeration system oil separator E Subcooling temperature of refrigerant <![CDATA[T a ]]> Mass flow rate of the refrigeration system <![CDATA[Q m ]]> Liquid outlet flow rate of oil distillation unit <![CDATA[Q e ]]> Mass flow rate of oil in refrigeration system F Enthalpy reduction of refrigerant in oil distillation unit <![CDATA[H d ]]> Oil extraction rate P Enthalpy of refrigerant at the liquid outlet of the oil distillation unit <![CDATA[H e ]]> Steady-state lubricant target concentration C The temperature of the refrigerant at the liquid outlet of the oil distillation unit <![CDATA[T b ]]> Target oil recovery <![CDATA[F a ]]> Heat exchange temperature difference of oil distillation unit <![CDATA[T d ]]> Mass flow rate of oil distillation unit <![CDATA[Q r ]]> DETAILED DESCRIPTION

[0056] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0057] The terms "installed," "disposed," "provided with," "connected," and "connected" should be interpreted broadly. For example, they can refer to fixed connections, removable connections, or integral structures; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; or internal communication between two devices, elements, or components. Those skilled in the art will understand the specific meanings of these terms in the present invention based on specific circumstances.

[0058] Furthermore, the terms "first," "second," etc., are primarily used to distinguish between different devices, elements, or components (which may or may not be of the same type and configuration), and are not intended to indicate or imply the relative importance or quantity of the devices, elements, or components indicated. Unless otherwise specified, "plurality" means two or more.

[0059] It should be noted that the terms "including" and "having" and any variations thereof in the embodiments of the present invention are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or devices.

[0060] The technical solution of the present invention will be further described below in conjunction with embodiments and drawings.

[0061] Example 1

[0062] See also Figure 1 and Figure 4 , Figure 1 1 is a flow chart of a method for determining the heat exchange capacity of an oil rectification device in a refrigeration system provided in Example 1 of the present invention. Figure 4 FIG. 1 is a schematic diagram of the structure of the refrigeration system 100. Figure 1 As shown, the method for determining the heat exchange capacity of the oil rectifier of the refrigeration system may include:

[0063] 101. Obtain the following parameters: operating parameters of the refrigeration system and the oil discharge volume E of the oil separator of the refrigeration system.

[0064] In the embodiment of the present invention, the operating parameters of the refrigeration system include the refrigeration capacity R of the refrigeration system. c , the evaporation temperature of the refrigeration system, and the evaporation heat H of the refrigerant in the refrigeration system at the evaporation temperature v Among them, the heat of evaporation H v It means that according to the type of refrigerant in the refrigeration system, by consulting the thermodynamic performance table of the refrigerant, the evaporation heat H of the refrigerant at the evaporation temperature can be obtained. v The operating parameters of the refrigeration system can be obtained by selecting the refrigeration system at the beginning of the design. It should be noted that the selection of the refrigeration system is related to the cooling capacity required by the place where the refrigeration system is to be used, and the cooling capacity generated by the refrigeration system can meet the cooling capacity required by the place where the refrigeration system is to be used.

[0065] See also Figure 4 The refrigeration system 100 includes a compressor 10, an oil separator 20, a condenser 30, a liquid storage tank 40, an oil rectifier 50, a throttling device 60, a circulation barrel 70, a pump body 80 and an evaporator 90.

[0066] The oil discharge capacity E of a refrigeration system's oil separator is the ratio of the mass of lubricating oil mixed with the refrigerant gas discharged from the gas outlet 21 of the oil separator 20 after separation to the mass of the refrigerant in the refrigeration system. The oil discharge capacity E of the oil separator can be determined based on the type of oil separator 20 selected.

[0067] 102. According to the operating parameters of the refrigeration system, obtain the mass flow rate Q of the refrigeration system m .

[0068] Specifically, the mass flow rate Q of the refrigeration system m The calculation formula is:

[0069] Q m =R c / H v ;

[0070] Among them, R c is the cooling capacity of the refrigeration system, in kW, H v The heat of evaporation of the refrigerant in the refrigeration system, in kJ / kg. The mass flow rate Q of the refrigeration system m It refers to the mass flow rate of refrigerant in the refrigeration cycle, measured in kg / s.

[0071] 103. According to the oil discharge amount of the refrigeration system oil separator and the mass flow rate of the refrigeration system, the mass flow rate F of the oil in the refrigeration system is obtained.

[0072] Specifically, the calculation formula for the mass flow rate F of oil in the refrigeration system is:

[0073] F=Q m *E;

[0074] Where E is the oil discharge volume of the oil separator in the refrigeration system.

[0075] 104. Set the oil extraction rate P and the steady-state lubricating oil target concentration C.

[0076] The oil extraction rate P refers to the ratio of the mass of liquid extracted from the liquid in the circulation drum 70 by the oil rectifier 50 to the total amount of liquid in the circulation drum 70. The steady-state lubricating oil target concentration C refers to the steady-state concentration of lubricating oil mixed in the refrigerant in the refrigeration cycle.

[0077] 105. According to the oil extraction rate P, steady-state lubricating oil target concentration C, and the mass flow rate Q of the refrigeration system m , obtain the target oil recovery F a , and the target oil recovery volume F a Greater than the mass flow rate F of the oil.

[0078] Specifically, the target oil recovery amount F a The calculation formula is:

[0079] F a =Q m *P*C;

[0080] Where C is the target concentration of steady-state lubricating oil, F aIt refers to the mass flow rate of the extracted and recovered lubricating oil set for the oil rectifier 50, and its unit is kg / s.

[0081] By setting the oil extraction rate P and the steady-state lubricating oil target concentration C, and making the target oil recovery amount F a The flow rate F is greater than the mass flow rate of oil, so that the mass of lubricating oil recovered by the oil rectifier 50 per unit time can exceed the amount of lubricating oil discharged from the gas outlet 21 of the oil separator 20. Thus, after several refrigeration cycles, the lubricating oil discharged from the oil separator 20 into the refrigeration cycle is gradually extracted by the oil rectifier 50 and re-inhaled into the compressor 10, thereby reducing the amount of lubricating oil remaining in the refrigeration cycle. This, on the one hand, reduces the adverse effects of the lubricating oil on the efficiency of the evaporator 90 and improves the heat exchange efficiency of the evaporator 90. On the other hand, it ensures that there is sufficient lubricating oil inside the compressor 10 to maintain its operation.

[0082] 106. According to the mass flow rate Q of the refrigeration system m and the oil extraction rate P, to obtain the mass flow rate Q of the oil distillation unit r .

[0083] Specifically, the mass flow rate Q of the oil distillation unit is r The calculation formula is:

[0084] Q r =Q m *P;

[0085] Among them, the mass flow rate Q of the oil distillation unit is r It refers to the mass flow rate of the refrigerant flowing through the oil rectifier 50, and its unit is kg / s.

[0086] 107. According to the mass flow rate Q of the oil distillation unit r and the operating parameters of the refrigeration system to obtain the heat transfer capacity K of the oil distillation unit.

[0087] Specifically, the calculation formula for the heat exchange capacity K of the oil distillation unit is:

[0088] K=Q r *H v ;

[0089] Among them, the heat exchange capacity K of the oil distillation unit is kJ / s.

[0090] By determining the heat exchange capacity K of the oil rectifier, an oil rectifier 50 with a corresponding heat exchange power can be selected based on the heat exchange capacity K. In this way, the oil rectifier 50 can evaporate all the liquid extracted from the circulation barrel 70 and suck it into the compressor 10 in the form of gas for reuse. The liquid includes refrigerant and lubricating oil mixed in the refrigerant. By calculating the heat exchange capacity K of the oil rectifier, the selection of the oil rectifier can be guided, so that an oil rectifier with appropriate power can be selected for the refrigeration system, avoiding waste or reduced refrigeration efficiency caused by excessive heat exchange capacity of the oil rectifier 50, and avoiding insufficient evaporation caused by insufficient heat exchange capacity of the oil rectifier 50, which leads to the problem of liquid inhalation by the compressor 10.

[0091] In addition, the method for determining the heat exchange capacity of the oil distillation device can be applied to but not limited to refrigeration systems using carbon dioxide, Freon or halogenated hydrocarbons as refrigerants, such as carbon dioxide cascade systems or flooded halogenated hydrocarbon refrigeration systems, and the liquid supply method can be barrel pump supply.

[0092] Example 2

[0093] like Figure 2 As shown, the second embodiment of the present invention provides a method for determining the heat exchange temperature difference of an oil rectifier in a refrigeration system, comprising:

[0094] 201. Obtain the enthalpy value H of the refrigerant at the liquid inlet of the oil distillation unit L and the subcooling temperature T of the refrigerant a .

[0095] Specifically, the enthalpy of the refrigerant at the liquid inlet of the oil distillation device is H L It refers to the enthalpy value of the refrigerant at the liquid supply inlet 511 of the oil distillation unit 50, and the unit is kJ / kg. This value can be obtained by using the temperature of the refrigerant at the liquid supply inlet 511 and referring to the thermodynamic performance table of the refrigerant. Liquid supply subcooling temperature T a It refers to the temperature of the refrigerant at the liquid supply inlet 511 of the oil distillation device, in °C, which can be obtained by selecting the refrigeration system at the beginning of the design.

[0096] 202. According to the mass flow rate Q of the oil distillation unit r , obtain the liquid outlet flow rate Q of the oil distillation unit e .

[0097] Specifically, the liquid outlet flow rate Q of the oil distillation unit is e The calculation formula is:

[0098] Q e =Q m -Q r ;

[0099] Among them, Q m is the mass flow rate of refrigerant in the refrigeration system, Qr is the mass flow rate of refrigerant in the oil distillation unit.

[0100] 203. According to the liquid outlet flow rate Q of the oil distillation unit e , obtain the enthalpy reduction of the refrigerant in the oil distillation unit H d . The enthalpy reduction of the refrigerant in the oil distillation unit H d It refers to the amount of enthalpy reduction on the first heat exchange side 51 of the oil rectifier 50 due to heat exchange with the second heat exchange side 52 , and the unit is kJ / kg.

[0101] Specifically, the enthalpy reduction H d The calculation formula is:

[0102] H d =K / Q e ;

[0103] Among them, K is the heat exchange capacity of the oil distillation unit, Q e is the liquid outlet flow rate of the oil distillation unit.

[0104] 204. According to the enthalpy reduction of the refrigerant in the oil distillation unit H d and the enthalpy of the refrigerant at the liquid inlet of the oil distillation device H L , obtain the enthalpy value H of the refrigerant at the liquid outlet of the oil distillation device e .

[0105] Specifically, the enthalpy value H of the refrigerant at the liquid outlet of the oil rectifier is e The calculation formula is:

[0106] H e =H L -H d ;

[0107] Among them, H L is the enthalpy of the refrigerant at the liquid inlet of the oil distillation device, H d It is the enthalpy reduction of the refrigerant in the oil distillation unit.

[0108] 205. According to the enthalpy value H of the refrigerant at the liquid outlet of the oil distillation device e and the subcooling temperature T of the refrigerant a , calculate the heat exchange temperature difference T of the oil distillation unit d .

[0109] Specifically, the heat exchange temperature difference T d The calculation formula is:

[0110] T d =T a -T b ;

[0111] Among them, T a is the subcooling temperature of the refrigerant, T b The enthalpy value H of the refrigerant at the liquid supply outlet 512 of the oil rectifier 50 can be obtained by referring to the thermodynamic performance table of the refrigerant in the refrigeration system. e The corresponding temperature T b .

[0112] In this embodiment, the method for determining the heat exchange capacity K of the oil rectification device is the same as that in the first embodiment, and will not be repeated here.

[0113] By determining the heat exchange temperature difference T of the oil distillation d , together with the heat exchange amount K of the oil rectifier, the oil rectifier 50 can be selected more accurately, so that the oil rectifier 50 can be selected according to the heat exchange temperature difference T d , the heat exchange amount K is selected to be suitable for the oil rectifier 50 so that the various performances of the oil rectifier 50 can better adapt to the requirements of the refrigeration system 100 and improve the reliability of the operation of the refrigeration system 100.

[0114] Example 3

[0115] See also Figure 3 A third embodiment of the present invention provides an oil rectifier 50. The oil rectifier 50 includes a first heat exchange side 51 and a second heat exchange side 52, each of which is independent of the other. The first heat exchange side 51 includes a liquid supply inlet 511 and a liquid supply outlet 512, and the second heat exchange side 52 includes an oil intake port 521 and an oil outlet 522. The first heat exchange side 51 and the second heat exchange side 52 are capable of heat exchange. The heat exchange capacity of the oil rectifier 50 is determined based on the heat exchange capacity determination method for an oil rectifier in a refrigeration system described in the first embodiment.

[0116] By utilizing the oil rectifier 50 , the liquid mixture (including the refrigerant and a small amount of lubricating oil mixed in the refrigerant) flowing through the second heat exchange side 52 absorbs the heat provided by the first heat exchange side 51 , and the refrigerant in the liquid mixture is completely evaporated into gas and sucked into the compressor 10 , and the lubricating oil mixed in the refrigerant is also sucked into the compressor 10 , and plays a lubricating role for the compressor 10 again.

[0117] The heat exchange capacity determination method described in Example 1 can be used to calculate the heat exchange capacity required by the oil rectifier 50 in the refrigeration system, converting all liquid on the second heat exchange side 52 into gas and preventing the problem of liquid carryover from the compressor 10. Based on this calculation result, the oil rectifier 50 is selected to have the appropriate heat exchange capacity to meet the lubricating oil extraction requirements of the refrigeration system 100.

[0118] Optionally, the heat exchange temperature difference of the oil rectifier 50 may be determined based on the method for determining the heat exchange temperature difference of the oil rectifier in the refrigeration system in the second embodiment.

[0119] Optionally, the oil rectifying device 50 may be a plate heat exchanger or a shell and tube heat exchanger.

[0120] Example 4

[0121] See also Figure 4 Embodiment 4 of the present invention provides a refrigeration system 100, including a compressor 10, an oil separator 20, a condenser 30, a liquid storage tank 40, an oil distillation device 50, a throttling device 60, a circulation barrel 70, a pump body 80 and an evaporator 90.

[0122] The compressor 10 has an air inlet 11 and an air outlet 12. The oil separator 20 is connected to the compressor's air outlet 12. The condenser 30 is connected to the oil separator 20. The liquid reservoir 40 is connected to the condenser 30. As described in Example 3, the oil rectifier 50 has a liquid supply inlet 511 connected to the liquid reservoir 40, and an oil outlet 522 connected to the compressor 10. The throttling device 60 is connected to the liquid supply outlet 512 of the oil rectifier 50. The circulating barrel 70 has a liquid supply inlet 71, a liquid outlet 72, an air outlet 73, an air return port 74, and an oil drain port 75. The liquid supply inlet 71 is connected to the throttling device 60. The oil drain port 75 is connected to the oil extraction port 521 of the oil rectifier 50 to drain oil into the oil rectifier 50. The air outlet 73 is connected to the air inlet 11 of the compressor 10. The pump body 80 is connected to the liquid outlet 72 of the circulation barrel 70 , and the evaporator 90 is connected to the pump body 80 and the air return port 74 of the circulation barrel 70 .

[0123] The operation process of the refrigeration system 100 is as follows:

[0124] After the refrigerant performs work in the compressor 10, it forms a high-pressure gas, which is discharged from the exhaust port 12 of the compressor 10. This gas contains gaseous refrigerant and lubricating oil. The compressor 10 is connected to the oil separator 20 via corresponding piping. The high-pressure gas enters the oil separator 20 and is separated. A portion of the lubricating oil mixed in the gas is discharged from the liquid outlet 22 of the oil separator 20 and re-enters the compressor 10 through piping for use. Simultaneously, the gas outlet 21 of the oil separator 20 discharges a mixed gas containing gaseous refrigerant and a portion of the gaseous lubricating oil mixed with the refrigerant. This mixed gas then passes through the condenser 30 and the liquid reservoir 40, before entering the liquid supply inlet 511 of the oil rectifier 50 and exiting through the liquid supply outlet 512. The mixed gas flows through the first heat exchange side 51 of the oil rectifier 50, providing heat to the second heat exchange side 52. After leaving the oil rectifier 50, the mixed gas passes through the throttling device 60 to form a gas-liquid mixture, and enters the circulation drum 70 through the liquid supply port 71. The circulation drum 70 separates the gas-liquid mixture, with the liquid refrigerant entering the pump body 80 through the liquid outlet 72. The pump body 80 then transports the refrigerant to the evaporator 90. The refrigerant in the evaporator 90 becomes gaseous (contains liquid refrigerant if evaporation is insufficient) and enters the circulation drum 70 through the return air port 74. The gaseous refrigerant in the circulation drum 70 leaves the circulation drum 70 through the air outlet 73 and enters the compressor 10 through the air inlet 11. The compressor compresses the gaseous refrigerant to perform work, thus forming a refrigeration cycle.

[0125] At the same time, a portion of the liquid in the circulation drum 70 is extracted through the oil drain port 75 and transferred to the oil rectifier 50. The oil rectifier 50 receives the liquid (a mixture of liquid refrigerant and lubricating oil) from the circulation drum 70 through the oil extraction port 521 and outputs it through the oil outlet 522. In the oil rectifier 50, the liquid passes through the second heat exchange side 52, where it evaporates using the heat provided by the first heat exchange side 51. The liquid refrigerant evaporates into gas, which is then drawn away by the compressor 10 and re-enters the refrigeration cycle. Simultaneously, the lubricating oil mixed with the liquid is also drawn away by the compressor 10 and reused.

[0126] Through the refrigeration cycle of the above-mentioned refrigeration system 100, on the one hand, the refrigerant is alternately transformed into gas and liquid in the refrigeration cycle to achieve the refrigeration function. On the other hand, after the lubricating oil is discharged from the compressor 10, it is extracted and separated by the oil distillation device and then re-enters the compressor 10 to provide lubrication for the operation of the compressor 10, thereby reducing the retention of the lubricating oil in the evaporator 90, improving the working conditions of the evaporator 90 and increasing the evaporation efficiency, thereby increasing the reliability of the operation of the compressor 10 and thus increasing the reliability of the refrigeration system 100.

[0127] By selecting an oil rectifier determined based on the method for determining the heat exchange amount in the first embodiment, or an oil rectifier determined based on the method for determining the heat exchange temperature difference of the oil rectifier in the second embodiment, and applying it to the refrigeration system 100, as the number of refrigeration cycles increases during the operation of the refrigeration system 100, the content of lubricating oil in components other than the compressor 10 of the refrigeration system 100 can be gradually reduced, thereby reducing the adverse effects of lubricating oil retention on other components, while ensuring that there is sufficient lubricating oil inside the compressor 10, thereby improving the reliability of the operation process of the compressor 10.

[0128] Optionally, the throttling device 60 includes but is not limited to an expansion valve, a capillary tube, and a throttling tube. The pump body 80 can be a fluorine pump or the like.

[0129] The evaporator 90 can be set up one or more according to the actual application scenario. When multiple evaporators 90 are set up, the multiple evaporators 90 can be set up in parallel (such as Figure 5 shown).

[0130] The above is a detailed introduction to the method for determining the heat exchange rate of an oil rectifier in a refrigeration system, the oil rectifier, and the refrigeration system disclosed in the embodiments of the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only intended to help understand the method for determining the heat exchange rate of an oil rectifier in a refrigeration system, the oil rectifier, the refrigeration system, and their core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A method for determining the heat exchange capacity of an oil distillation unit in a refrigeration system, characterized in that: include: Obtain the following parameters: operating parameters of the refrigeration system and the oil discharge volume E of the refrigeration system oil separator; According to the operating parameters of the refrigeration system, the mass flow rate Q of the refrigeration system is obtained. m ; According to the oil discharge volume E of the refrigeration system oil separator and the mass flow rate Q of the refrigeration system m , obtaining the mass flow rate F of the oil in the refrigeration system; Set the oil extraction rate P and the steady-state lubricating oil target concentration C; According to the oil extraction rate P, the steady-state lubricating oil target concentration C, the mass flow rate Q of the refrigeration system m , obtain the target oil recovery F a , and the target oil recovery volume F a Greater than the mass flow rate F of the oil; According to the mass flow rate Q of the refrigeration system m and the oil extraction rate P, to obtain the mass flow rate Q of the oil distillation unit r ; According to the mass flow rate Q of the oil distillation unit r and the operating parameters of the refrigeration system to obtain the heat transfer capacity K of the oil distillation unit.

2. The method for determining the heat exchange capacity of an oil rectifier in a refrigeration system according to claim 1, wherein: The operating parameters of the refrigeration system include the refrigeration capacity R of the refrigeration system c , the evaporation temperature of the refrigeration system, and the evaporation heat H of the refrigerant in the refrigeration system at the evaporation temperature of the refrigeration system v .

3. The method for determining the heat exchange capacity of an oil rectifier in a refrigeration system according to claim 2, wherein: The mass flow rate Q of the refrigeration system m for: Q m =R c / H v ; Among them, R c is the cooling capacity of the refrigeration system, H v is the evaporation heat of the refrigerant in the refrigeration system.

4. The method for determining the heat exchange capacity of an oil rectifier in a refrigeration system according to claim 3, wherein: The mass flow rate F of the oil in the refrigeration system is: F=Q m *E; Wherein, E is the oil discharge capacity of the oil separator in the refrigeration system.

5. The method for determining the heat exchange capacity of an oil rectifier in a refrigeration system according to claim 3, wherein: The target oil recovery amount F a for: F a =Q m *P*C; Where P is the oil extraction rate and C is the steady-state target lubricating oil concentration.

6. The method for determining the heat exchange capacity of an oil rectifier in a refrigeration system according to claim 3, wherein: The mass flow rate Q of the oil distillation unit r for: Q r =Q m *P。 7. The method for determining the heat exchange capacity of an oil rectification device in a refrigeration system according to claim 6, characterized in that: The heat exchange K of the oil rectifier is: K=Q r *H v 。 8. The method for determining the heat exchange capacity of an oil rectification device in a refrigeration system according to claim 6, wherein: include: Obtain the enthalpy value H of the refrigerant at the liquid inlet of the oil distillation device L and the subcooling temperature T of the refrigerant a ; According to the mass flow rate Q of the oil distillation unit r , obtain the liquid outlet flow rate Q of the oil distillation unit e ; According to the liquid outlet flow rate Q of the oil rectifier e , obtain the enthalpy reduction of the refrigerant in the oil distillation unit H d ; According to the enthalpy reduction H of the refrigerant in the oil distillation device d and the enthalpy of the refrigerant at the liquid inlet of the oil distillation device H L , obtain the enthalpy value H of the refrigerant at the liquid outlet of the oil distillation device e ; According to the enthalpy value H of the refrigerant at the liquid outlet of the oil distillation device e and the subcooling temperature T of the refrigerant a , calculate the heat exchange temperature difference T of the oil distillation unit d .

9. An oil distillation device, characterized in that: The oil rectifier comprises a first heat exchange side and a second heat exchange side which are independent of each other, wherein the first heat exchange side comprises a liquid supply inlet and a liquid supply outlet, and the second heat exchange side comprises an oil intake port and an oil outlet, and the first heat exchange side and the second heat exchange side are capable of heat exchange; The heat exchange capacity of the oil rectifier is determined based on the method for determining the heat exchange capacity of the oil rectifier in a refrigeration system according to any one of claims 1 to 8.

10. A refrigeration system, characterized in that: include: a compressor having an air inlet and an air outlet; an oil separator connected to the exhaust port of the compressor; a condenser, the condenser being connected to the oil separator; a liquid reservoir connected to the condenser; The oil rectifier according to claim 9, wherein the liquid supply inlet is connected to the liquid reservoir, and the oil outlet is connected to the compressor; a throttling device connected to the liquid supply outlet of the oil rectifier; a circulation barrel, the circulation barrel having a liquid supply port, a liquid outlet port, an air outlet port, an air return port, and an oil drain port, the liquid supply port being connected to the throttling device, the oil drain port being connected to the oil extraction port of the oil rectifier to drain oil into the oil rectifier, and the air outlet port being connected to the air inlet port of the compressor; a pump body, the pump body being connected to the liquid outlet of the circulation barrel; and An evaporator is connected to the pump body and the air return port of the circulation barrel.

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